Carbon dioxide refrigerating apparatus



June 13, 1950 Q E, QUINN 2,511,176

CARBON DIOXIDE REFRIGERATING APPARATUS /X//I/I/f//f/ Jun 13, 1950 c. E. QUINN CARBON 1110x1111: REFRIGERATING APPARATUS 2 Sheets-Sheet 2 Filed Feb. 26, 1946 INVENTOR. C/ara E. Quinn BY %M1yfy Patented June 13, 1950 CARBON DIOXIDE REFRIG'ERTING' APPARATUS' Clara E. Quinn, St. Petersburg, Fla., assigner to Frank S. Reed, St. Petersburg, Fla.

Application February 26, 1946, Serial-Nm 650,217?

9 Claims.

This invention relates to improvements in refrigerating4 apparatus of the type employing a solid refrigerant as the source. of refrigeration, as for example solid carbon dioxide..

A broad object of this inventionis to provide animproved system. forl utilizing solid carbon:y

dioxide as the source of refrigeration forl railway cars, trucks and the like;

An object-of the. invention is to provide a system for more eiiciently effecting thetransfer of heat from the space to be refrigerated to.` the solid carbon dioxide bunker for absorption thereby.

An object of this invention is to provide a system of this type employing a; liquid circulatory secondary refrigerant moving between the point of heat absorption from the space to be refrigerated to the point o'f transfer of heat to the refrigerant.

Another object of the invention is to provide two or more double Walled heat conducting bunkers for the solid carbon dioxide interconnected with the cooling plates or coils in such a manner that theY secondary refrigerant will have a maximum contact timewith the heat exchange Wall throughwhich it gives. up its absorbed heat toV the refrigerant.

A moreY speci-lc object of the invention` is to provide a double walled container construction of this typeof such form as to permit of the use of metalv walls of minimum. thickness while attaining. maximum. strength.

Other and more detailed4 objects of. the invention will :beV apparent from: the following description of the embodiment thereof illustrated in the attached drawings.

This invention resides substantially in the combination, construction, arrangement and relative location of parts, all as will be described in. detail below.

In the accompanying drawings,

Figure 1 is a top planview of the apparatus of this invention showing the insulating housing in cross-section; and

Figure 2 is a cross-sectional view takenon the line 2--2 of Figure. l.

The insulating housing which may be a refrigerating cabinet, the wallof a railway car, or the wall of a truck, for example, is shown in part in the figures as comprising an end wall I0, side walls II, a partition I2, andl a roof I3 made of any suitable heat insulating material and.

forming a closed cabinet or space for the solid carbondioxide. bunkers. The` partition I2 has been omitted'` fromv Figure. 2 but its position is Iapparent from Figure 1. The sol-id carbon dioxideY bunkersv comprise' thev double wallv vessels I4 and- |5- and It and. Il: forming theY closed chambers B and A respectively.. These bunkers can bef made of any suitable heat conducting material', preferably' metal, and1 are shown. as having an oval form inv cross-section to provide maximum strength. They can, for example, be made elliptical or spherical in form to provide other suitablevessel` shapes. As al result-of these forms the metal walls may be made of a minimum thickness. to withstand the mechanical loading andY gas iiuid pressures to which they will normally bev subjected, tot facilitate rapid heat transfer therethrough.

As is clear from. Figuren 1, each of the vessels I to II` inclusive is closed atv all sides to form hermetically sealed containers and the inner containers can be supported within the outer containers by any suitable formy of spacing means,l not shown. Extending between suitable openings in the roof I3 andY the cabinet are hatchesv I8, I9; 2-2 and 2lil having removable closures 20, 2l, 23 and 25. The hatches extend through the outer vessels i5' and I1 at sealed joints and open` intov the inner vessels I4 and I6, forming therewith overall sealed connections. For example, these hatches may be made of metal and be 'welded in place in the double wall containers. It will be seen from. Figure 1 that a hatch is provided for each. end' of each bunker to facilitate proper filling of each bunker formed by the inner containersV I4 and It with solid carbon dioxide which isdiagrammatically illustrated in Figure: 2 by the reference character DI.

The spaces defined by the inner containers I4 and I6 are interconnected by pressure equalizing carbon dioxide gas conduit 26', see Figure 2. Supported above the bunkers-inv any suitable manner, as for'example in a recessin' the roof of the cabinet, is a container 21 having a lling connection and removableY cap 28 accessible from the top of the container.V A branch pipe'29 connects the container 21 with the chambers A and B.

Extending along each side of the cabinet are thin, plate-like cooling members 3I which may be thin, plate-like hollow, hermetically sealed containers of metal. If desired a series of cooling coils or other forms of heat exchangers can be used.

Referringv to Figure 2, the upper end of one cooling member 3l is. connected by a conduit 32 with the chamber A at one end and the lower end of the member 3| is connected by means of the conduit 30 with the chamber B. Similarly, at the other end, as is clear from Figure 2, the other cooling member will be connected at its upper side to the chamber B by means of conduit 36, and at its lower side to the space A by means of the conduit 35. As shown in Figure 1, conduits 32 and 36 are provided with valves 33 and 31 respectively, which are thermostatically controlled by means of the temperature sensitive bulbs 34 and 38 respectively. These bulbs are exposed to the space to be cooled so that the temperature therein will iniiuence the setting of the valves to control the flow of circulating cooling uid.

The circulating system comprising the chambers A and B, conduits 30, 32, 35 and 36, and cooling members 3I will form closed circulatory systems for the liquid secondary refrigerant which will completely ll the systems up to a level in the expansion tank 21. The amount of liquid in the system will not be sufficient to fill the expansion tank 21 so that While insuring that the system will be full at al1 times, provision is made for any change in volume of the liquid that may occur as the result of temperature changes. Additional liquid can be added as required through the lling connection by removing cap 28.

The operation of this system will be apparent, but it may be briefly reviewed. As the liquid in the cooling members 3| absorbs heat it rises and travels back to the chambers A and B through the conduits 32 and 35. It is discharged into these spaces at the top where it may move in heat exchange relation with inner Walls I4 and I6 to give up its heat to the solid carbon dioxide. The iluid entering the chamber A from the conduit 32 is ultimately delivered back to the opposite member through the delivery conduit 35 so that it must travel throughout the length of the chamber A before it is returned to the cooling member. This insures an e'icient extraction of heat therefrom 'by the associated solid carbon dioxide. In a similar way the fluid return from the other cooling member 3l is returned to the left hand end, Figure 1, of chamber B, and is delivered from the right hand end of this chamber to the supply conduit 3U 1and thence to the opposite member. Thus it will be seen that any unit of the liquid will alternately circulate through both members and must travel along the Walls I4 and I6 throughout their length at the time of heat discharge to the refrigerant.

The rate of flow of the cooling liquid which is moved under thermosiphonic action will be further controlled by means of the valves 33 and 31 which in turn will be opened and closed in response to temperature changes in the space being refrigerated.

Those skilled in the art will appreciate that the secondary refrigerating liquid may be any one of a ninnber of materials known and used for this purpose. Generally speaking, they should be liquids having large heat absorbing capacity which will not freeze under the conditions normally encountered in the operation of the system, and which will preferably, but not necessarily, remain in liquid state under these conditions.

It is equally clear that it is not necessary to use solid carbon dioxide as the refrigerant, but it is preferred for this system. The conduit 26 will serve to equalize gas pressure conditions within the bunkers themselves, that is within the spaces dened by the walls I4 and I5. No gas escape conduit is shown since it is assumed that closures for the hatches, but suitable members can be provided which may or may not include pressure responsive valves if desired.

From the above description it will be apparent to those skilled in the art that the subject matter of this invention is capable of some variation, and I do not, therefore, desire to be limited to the illustrative example given herein, but rather by the claims granted me.

What is claimed is:

1. In a refrigerating apparatus the combination including a heat insulated cabinet forming an apparatus and a storage compartment, a pair of elongated double-walled heat conducting vessels in said apparatus compartment, a pair of heat exchange members in said storage compartment, a return conduit from one of said members to one end of the space deiined by the walls of one of said vessels and a supply conduit from said member to the corresponding end of the space dened by the walls of the other vessel, a return conduit from the second member to the latter space at its opposite end, and a supply conduit connecting said second member with the former space at its other end, whereby a series liquid secondary refrigerant circuit is formed by the spaces of the double-wall vessels, the coils and conduits.

2. In a reirigerating apparatus as disclosed, a heat insulating cabinet forming an apparatus and a storage compartment, a pair of elongated double-walled heat conducting vessels in said apparatus compartment, the inner space of each forming a solid refrigerant bunker, a pair of heat exchange members in said storage compartment and connections between said members and the spaces formed by the walls of said vessels to cause a circulatory liquid secondary refrigerant to flow alternately through both refrigerating members and in so doing to travel throughout the length of the spaces deiined by said doublewalled vessels.

3. A refrigerating apparatus including a heat insulated cabinet forming an apparatus compartment and a storage compartment, a pair of double-walled heat conducting vessels in said apparatus compartment each forming a closed space, the chamber defined by the inner wall of each vessel providing a bunker for a solid refrigerant, a liquid circulatory system comprising a pair of hollow heat exchange plates disposed in said storage compartment, a supply connection and a return connection for each of said plates, said supply connections communicating respectively with said spaces at the opposite ends of said spaces and said return connections communicating respectively with said spaces at their other ends to form with said spaces closed circulatory systems, and a heat exchange liquid filling said systems whereby the liquid moving through said plates absorbs heat from the storage space and gives up that heat to the solid refrigerant in said bunkers while traveling lengthwise of said spaces.

4. In the combination of claim 3, hatches having removable closures through which a solid refrigerant may be introduced into said bunkers.

5. In the combination of claim 3, an expansion tank for said liquid communicating with both of said spaces.

6. In the combination of claim 3, a conduit Y establishing communication between said bunkers.

'1. In a refrigerating apparatus the combinathe necessary leakage can take place around the '(5' tion including a heat insulated cabinet divided into an apparatus compartment and a storage compartment, a pair of double-walled heat conducting vessels in said apparatus compartment each forming a closed space and extending throughout the width of said apparatus compartment, a pair of hollow heat exchange members lying along the sides of said storage compartment, a pair of conduits connecting one of said members with the adjacent ends of said spaces, a pair of conduits connecting the other member with said spaces at the other ends of said spaces; said hollow members, the conduits connected thereto and said spaces forming a closed circulatory system adapted to contain a liquid secondary refrigerant, and a conduit establishing communication between the innermost vessel of said pair of double-walled vessels.

8. In the combination of claim 7, a thermostatically controlled valve in one conduit of each vessels.

CLARA E. QUINN.

REFERENCES CITED The following references are of record in the file of this patent:

FOREIGN PATENTS Country Date Great Britain May 18, 1933 Number 

